In the steamy twilight of the jungle, Gilles Bokande hunkered beside a mossy stump and pinched his nose between his index and middle fingers. Blowing air through the back of his throat, he bleated like a duiker, a tiny forest antelope.

Nothing happened.Trudging a mile deeper into Africa's largest remaining rain forest, Bokande crouched and tried again. Still no response.

The animals don't come anymore when Bokande, a Baka Pygmy, calls them. A fresh logging road snakes nearby--a muddy funnel that siphons away not only the forest's primeval hardwoods but also thousands of wild animals poached for the dinner tables of urbanites in the burgeoning cities of Cameroon.

"It's harder to find antelope, gorillas, chimpanzees and elephants," said Bokande, a pleasant, wiry man whose teeth are filed to sharp little points. "The forest is getting quieter now."

Across Africa, a remorseless silence is falling over the far untamed corners of a continent that long has symbolized wild nature to a jaded, overindustrialized world.

In places such as the famed gorilla reserves of Uganda, where conservationists are desperately trying to link the needs of dwindling wildlife with those of land-hungry farmers, it is the silence of nature drowned out by the babble of human overpopulation. In countries such as Kenya and South Africa--which grimly lead the continent with 59 and 141 endangered species--it is the quiet absence of wild animals outside of zoolike national parks. And in hot spots like Angola and Congo, it is the pitiable hush that comes after the massacres of wild animals amid terrible civil wars.

But here, deep in the lush rain forests of central Africa, that deadened stillness is even more ominous because it heralds the outside world's final assault on the last true wilderness left on the continent. In a rain forest second only to the Amazon in size, environmentalists are girding themselves for one of the defining conservation battles of the 21st Century: saving an African frontier so wild that its animals don't run away because they have never seen humans before.

"This is the holy of holies," said World Wildlife Fund biologist Paul Noupa, one of the conservationists scrambling to set up wildlife sanctuaries so remote that they probably won't have visitors for years. "If we fail to preserve this place, we can only blame ourselves. All over Africa, you have a long history of conservation. Not here. Here we are starting from scratch, and the clock is ticking."

Until recently, time was of little consequence in the vast rain forest that stretches from Nigeria east to Rwanda.

About a third as big as the continental United States, it was a forgotten refuge for Africa's densest concentrations of animals and for the Pygmies who hunted them with arrows and spears. But since the early 1990s, a timber rush spearheaded by European logging companies has kicked off a classic story of greed and exploitation--a tale that includes an unprecedented slaughter of monkeys, an unseemly turf battle among conservation groups, and a cynical developed world that wants to have its rain forest and eat it too.

Logging and hunting have gone hand in sweaty hand in the Congo Basin for as long as anyone can remember. But both activities have exploded for reasons few could have foreseen.

The depletion of west Africa's forests, where Europe traditionally bought its tropical hardwoods, has launched a stampede of French, German and Middle Eastern logging companies into the more inaccessible jungles of central Africa. At the same time, a regional economic crisis has only accelerated the timber boom: Local currency devaluations in the mid-1990s effectively halved the cost of hauling 800-year-old trees through hundreds of miles of forest to the parquet-flooring and furniture-making markets of Europe and Japan.

In Cameroon, wood production soared 50 percent between 1992 and 1997, the last years for which figures are available.

Strapped for cash because of slumping cacao exports, the government has gratefully seized the $60 million-a-year lifeline created by logging revenues. The story is the same in neighboring Gabon, where declining oil production is stoking the logging trade and where the president, Omar Bongo, owns 500,000 acres of prime timber concessions.

But just as Mercedes-Benz logging trucks have begun rumbling in earnest along the Congo Basin's new mud highways, the public's appetite for wild animal meat surged in the teeming cities of Cameroon, Gabon, Congo and the Central African Republic.

Elephants, antelopes and monkeys have been a staple of local villagers' diets for millenniums, of course. But Africa's swelling urban populations, nostalgic for village foods and flush with money, have turned a subsistence activity into a burgeoning, multimillion-dollar industry.

Newly extended logging roads have become bush meat pipelines plied by poachers who snare and shoot anything in sight. Many logging companies encourage the hunting because it also saves on the cost of shipping beef into the remote jungle towns where their workers live.

"We know it's a problem, and we are even planning to raise a herd of cows for workers to eat," said Thibaut Fuchs, the sawmill manager of the Forestry Association of Cameroon, a French-Cameroonian logging company that selectively harvests mahogany, sapeli and ebony from 200,000 acres of jungle. "But it's an uphill battle. People here say, `You've got to be kidding! Why raise cows? The forest is ours, and the wild animals are everywhere!' "

In hundreds of town markets like the one in Yokadouma, a logging center set like a grubby island in the middle of southeastern Cameroon's oceanic canopy of trees, about a dozen vendors specialize in selling wild animal carcasses. Antelopes, skinned and trussed, look like small greyhounds frozen in mid-stride. Elephant meat is hacked into 2-pound cubes. And smoked sections of an animal's large intestine--possibly from a forest buffalo--look like a charred fire hose.